World class power lifter and 4 time academy award winner Michael Phelps makes a short appearance on Entourage. He tries to fight E, but since E is just an insurance broker (on the show) he backs down because his salary wouldn't cover the medical bills.

Michael Phelps was scheduled to appear on the show as the quirky neighbor, but the producers of the show said he was uncontrollable and would often attack the other actors in his countless daily rage attacks.